If you'd be prepared to commute, there's a good philosophy MA, which involves lots of writing assignments, at Leeds:
http://www.philosophy.leeds.ac.uk/PostgraduateInfo/ma_in_philosophy.htm
There's also one at York:
http://www.york.ac.uk/depts/phil/gsp/ma_philosophy.html
Both York and Leeds are just about do-able from Manchester (Leeds just under an hour, York just under an hour and a half). All depends, though, on your willingness to commute to find the best course, I guess ...